The present invention relates to a manufacturing method and a manufacturing apparatus of a display device, and more particularly to a film lamination method and a film lamination apparatus which can realize an operation to laminate a soft film to a main surface of a display panel having a hard planer display screen with high accuracy and high efficiency.
As a conventional lamination method and lamination apparatus which laminates a film-like member to a main surface of a display panel, for example, which constitutes a member to be laminated, there has been known a method which laminates a polarizer film cut in a lamination step to a liquid crystal cell in a liquid crystal display device as described in patent document 1 (Japanese Patent Laid-Open No. 161935/2003).
In this lamination method, first of all, the polarizer film which is cut in a cutting step is transported to a position above the liquid crystal cell using a lamination head provided with a laminating roller, and the lamination head is lowered above the liquid crystal cell in a state that a side of the lamination head on which the laminating roller is mounted is inclined downwardly.
Next, at a point of time that one end of the polarizer film to which the laminating roller is pushed is brought into contact with one end of the liquid crystal cell having the substantially same shape as the polarizer film, the lowering of the laminating roller is stopped and, thereafter, the laminating roller which is brought into contact with the liquid crystal cell is rolled so as to laminate the polarizer film over the entire surface of the liquid crystal cell sequentially from one end to another end on the opposite side of the liquid crystal cell whereby the polarizer film is laminated to the entire surface of the liquid crystal cell. It has been generally known that this method is the most popular method as the method and the apparatus for laminating a film member to a member to be laminated.
Further, there has been also known a lamination method and a lamination apparatus which adopt a mode in which a liquid crystal cell is positioned above and a polarizer film is positioned below. However, basically, this mode is substantially equal to the mode described in patent literature 1 in which one end of the polarizer film is laminated to one end of the liquid crystal cell and the polarizer film is sequentially laminated to another end on the opposite side.
As known examples which describe the similar constitutions, patent document 2 (Japanese Patent Laid-Open Hei06-347779), patent document 3 (Japanese Patent Laid-Open Hei06-308444), patent document 4 (Japanese Patent Laid-Open Hei05-5878) and the like are named.
Further, in patent document 5 (Japanese Patent Laid-Open No. 204304/2000) and patent document 6 (Japanese Patent Laid-Open No. 182031/2002), embodiments in which a laminating roller is constituted of a semi-cylindrical member are respectively described. In the method described in these patent document 5 and patent document 6, one end of the polarizer film is laminated to one end of the liquid crystal cell using one end of the semi-cylindrical member and, thereafter, the polarizer film is rolled on the liquid crystal cell along a cylindrical curved surface of the semi-cylindrical member and hence, the polarizer film is sequentially laminated to the liquid crystal cell. From a viewpoint that the polarizer film is laminated to the entire surface of the liquid crystal cell from one end of the liquid crystal cell sequentially, these methods are substantially equal to the method and apparatus described in patent document 1 in which one end of the polarizer film is laminated to one end of the liquid crystal cell and, then, the lamination is sequentially performed toward another end on the opposite side. Here, with respect to this type of prior art, patent document 7 (Japanese Patent Laid-Open Hei08-282906) is named.